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rrsolis
10-24-2004, 04:03 PM
I have a 300 frame animation that want to render in fprime, so what I did was, once everything was setup how l wanted it, l did 15 aleatory frame renders (not previews) to check the time each took, and every single one was under two minutes for a quality level of 12 (the single frames were render as bmp24). So l figured that it was ok to render the whole sequence and have it stopped at the same quality of 12, the only difference is that l saving the files in RLA format instead of BMP. Now, this morning after more than 14 hours l find out that the average of the sequence is 1.5, and is just rendering the range 1-2 for the whole thing, in other words, some of the frames are still just at level 1 in quality, after so many hours the math just doesn't ad up, it should be finished by now.

Do you have any explanation and ideas why this is happening?

Thanks!

Triple G
10-24-2004, 09:53 PM
If you have objects which get very close to the camera (especially if you have Motion Blur turned on), this will cause certain frames to take longer than others. I've found that with FPrime, the "Stop at Level" command is not a hard and fast rule, but more of a general guide. Depending on things like motion blur, DOF, and object proximity to the camera, I've had situations where I've told it to stop at say level 5 and it continues on until 10 or 12 before it decides to move on. :shrug:

rrsolis
10-24-2004, 10:07 PM
Triple G: Since the scene is about the camera traveling kind of fast over a lab table, there are certain parts where it gets pretty close to objects, so that makes sense according to your experience. The thing that striked me off was that some of the frames I checked were exactly at the point where the camera is close to test tubes and stuff. So l figured that those frames were representative of the longest time that fprime would take to render a single frame, so l based my calculations of render time based on those, man, was l wrong!

Thanks!

Qexit
10-25-2004, 12:49 AM
the "Stop at Level" command is not a hard and fast rule, but more of a general guide. :shrug: Actually, that's an FPrime bug. 'Stop at Level' doesn't work, so you have to use the workaround of rendering a single frame to the level you want to 'Stop at', then reset the FPrime Render panel to render the complete set of frames required using the equalise option.

Triple G
10-25-2004, 02:13 AM
Ahhh....that explains it then. I always thought that was kind of weird. Thanks for clearing that up, Kevin. :)

ColinCohen
10-25-2004, 02:30 AM
Has someone told them about this problem?

I guess this means you can't render a scene using Classic Non-Refinable mode, as I presume it uses those data files to determine the equilization level.

rrsolis
10-25-2004, 02:32 AM
Thanks for the info Kevin! :)

Triple G
10-25-2004, 03:53 AM
I guess this means you can't render a scene using Classic Non-Refinable mode, as I presume it uses those data files to determine the equilization level.

I can't say for sure as I haven't done any definitive tests, but if I recall correctly, Classic Non-Refinable mode works as expected...input the Stop at Level number, and that's what it does...it simply stays with that frame and keeps rendering until it reaches the desired level, then it moves on to the next frame. I think it's only when you use Stop at Level without using CNR that it seems to ignore your input number. Like I said, I'm not 100% sure on this as I've never made any official notes on the problem.

ColinCohen
10-25-2004, 04:12 AM
I just tried rendering a blank scene with CNR set a 2, and it seemed to render the images at something like 10-12.

This could be an issue when rendering a large scene at a high resolution, as those data files eat a lot of space.

gerardo
10-25-2004, 04:25 AM
Even in that way I have noticed also that the FPrime window is quicker than FPrime Render.



Gerardo

Qexit
10-25-2004, 09:46 AM
Has someone told them about this problem?

I guess this means you can't render a scene using Classic Non-Refinable mode, as I presume it uses those data files to determine the equilization level. Worley is aware of the problem.

Also, Classic non-refinable mode does not create any data files. That's the whole point behind using it :) It renders each frame up to the desired quality level then saves it to disk before moving on to the next frame. The large data files are only created so that progressive refinement rendering can operate as they store information about rendering on a specific frame up to any given point...if that makes sense.

Qexit
10-25-2004, 09:52 AM
Even in that way I have noticed also that the FPrime window is quicker than FPrime Render.
Gerardo That's because the FPrime Preview window renders use a lot of shortcuts, inlcuding not doing motion blur and DOF. This allows faster rendering but at the cost of lower quality and, in some ways, an incomplete image. This is explained at greater length in the FPrime on-line manual on the Worley site. Just remember that the FPrime window is intended as a Preview of the final render. Sometimes people forget this :thumbsup:

Netvudu
10-25-2004, 10:27 AM
Am I the only one who read the FPrime documentation, and understood that the levels showed on the Render are NOT correlative to those of the preview window?

Which means that 7 on the preview, might be the same as 2 or 3 on the FPrime render, hence it isn´t taking much longer. It´s just a different measure. I tested this with a glass-made über-refracting über-reflecting logo, which a level 7 looked ok, while at 2 or 3 looked terrible. I stopped the FPrime Render at 3 and it looked great. I could edit and show the final work without any problems.

...just my own experience with it...

Qexit
10-25-2004, 10:49 AM
Am I the only one who read the FPrime documentation, and understood that the levels showed on the Render are NOT correlative to those of the preview window?

You are quite correct in your interpretation :thumbsup:

ColinCohen
10-25-2004, 01:45 PM
Also, Classic non-refinable mode does not create any data files.Yes, I am aware of this. That was my point.

If it doesn't create the data files, that means it has no way of knowing what level it needs to equalize the frames. So, in essence, unless I'm mistaken, this mode is useless if you need to render an entire scene at a specific level.

ColinCohen
10-25-2004, 02:59 PM
Okay, the solution appears to be the following:

1. Render the first frame with the Stop At Level.
2. Click Stop When All Equal and then click CNR.
3. Render the entire sequence.

You only need those data files for the first frame.

Qexit
10-25-2004, 03:05 PM
Yes, I am aware of this. That was my point.

If it doesn't create the data files, that means it has no way of knowing what level it needs to equalize the frames. So, in essence, unless I'm mistaken, this mode is useless if you need to render an entire scene at a specific level. Hi Colin,

Not too sure what you are getting at here. The equalise option is not available when you use Classic Render Mode...and isn't needed. The problem with FPrime overshooting the refinement level you set only occurs if you have a very simple scene. What happens, is FPrime tries to be clever/helpful and if it can render a frame really quickly it will flick through several iterations pre-emptively. With an average to highly complex scene, this does not happen. I just ran a couple of tests and as you said a blank scene causes FPrime to overshoot toaround 12 iterations on every frame..but as soon as I switched to even a fairly simple scene this did not happen and FPrime stopped at the iteration I had set. Mr Worley is aware of the problem and it will be fixed in the next release (and no I don't know when that will appear).

gerardo
10-26-2004, 01:59 AM
You are quite correct in your interpretation :thumbsup:

Interesting; but I don't achieve so good results with spinning lights (area light). My impression is that LW offers better results for this (even in less time). Make this test:
Empty scene
Add a sphere on a floor.
Change the distant light by default to arealight (adjust the size)
Add a Null and rotate it 640 degrees in H (frame 1) MB: 50%
Parent arealight to Null
Enhanced Medium, F9
Then test with FPrime
Which are your results?



Gerardo

HowardM
10-26-2004, 02:07 PM
Am I the only one who read the FPrime documentation, and understood that the levels showed on the Render are NOT correlative to those of the preview window?

Yep, its approx 10 to 1, so if your Preview looks good at 10, the final Render will look good at 1.
:D

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